Conventionally, screen printing has generally been used to form electrodes of a photovoltaic cell element by coating a paste for forming the electrode onto a semiconductor substrate made of a silicon or the like having a p-n junction, and firing in an oxidizing atmosphere. The paste used is one in which a metal powder, glass frit, an organic vehicle, and the like are mixed and made into a condition that enables screen printing (refer to, for example, Japanese Laid-open Patent Publication No. 2009-246277).
However, when forming an electrode on the semiconductor substrate, if there is a small amount of glass frit in the paste, there tends to be poor contact between the semiconductor substrate and the electrode. On the other hand, if there is a lot of glass frit, cracking tends to occur in the surface of the semiconductor substrate below the electrode, and the electrode tends to peel away, starting from the point of the crack, in subsequent process steps.